Read OS-9 Disk
Read floppy disks written under a OS-9 level 1 environment on PC-based hardware.
OS-9 Hardware
Disk were written on a developement system for embedded application system consisting of
- 19" rack based system (GESPACs GESBUS bus system G-64)
- harddisk drive ST-251 (20MByte)
- floppy disk drive 5.25"
- floppy disk controller WD 1791
- capable of single (FM) and double (MFM) density format
- Cards:
- Telex Adapter (self developement)
- EPROM/RAM-Disk, backup battery buffered (self developement)
PC Hardware
- Pentium II 233MHz AGP/PCI/ISA mainboard
- Adaptec AHA-1542CF
ISA-card, only floppy controller is used, Linux recognises it as "post-1991 82077")
- 5 1/4" floppy disk drive (NEC, Epson or similar)
- ATAPI-CDROM
... to start a CDROM-based Linux distribution like Knoppix 3.4 - systems of this kind may not boot from SCSI-CDROM or even USB stick
BIOS Setup
- Onboard floppy controller: disabled
Adaptec AHA-1542CF
- Floppy controller:
Sometimes an add-on floppy card will have a 765-compatible floppy controller that supports FM. The Adaptec AHA1542CF SCSI hard disk controller includes a floppy disk controller on the same card that supports FM and works with both 300 RPM and 360 RPM drives; so do some other Adaptec cards. This card is easy to use; you just plug it into any spare ISA slot and disable your motherboard FDC.
- Card setup (switches):
- 1: off (open) Termination Software controlled
- 2-4: off-off-offIO Adresse 330h
- 5: off Floppy enable
- 6-8: on-on-off BIOS Adress D0000h
- Ctrl-A (SCSISelect) card BIOS settings:
- BIOS Information:
- Revision: 2.02
- Base Address: D0000h
- Firmware Information:
- Revision: B.0
- Checksum: A223h
- !Host Adapter Interrupt Channel: 10
- !Host Adapter DMA Channel: 7
- Host Adapter SCSI ID: 7
- Advanced Configuration Options
- Floppy Controller I/O Port 3F0-3F7
- INT 19h Support: ENABLE
- everthing else: ENABLE
- Support Removeable Disks Under BIOS as Fixed Disks: D
booting and OS support
Booting with a Linux live CD:
- Knoppix 3.4 (Kernel 2.4)
- Boot prompt:
knoppix noscsi
This is needed if the boot procedure seems to hang because the aha1542.o module probing take a lot of time ...
Software
- [fdutils] (included on Knoppix distros)
needed commands:
- fdrawcmd (directly read sectors and tracks)
- floppycontrol (initialize/reset the controller)
- [os9disk (modified)] (supports FM tracks, bugfixes)
Extracting Data
ToDo?